Simplified adjustable magnetic head assembly



Aug- 3, 1954 E. z. GABRIEL SIMPLIFIED ADJUSTABLE MAGNETIC HEAD ASSEMBLY Filed April 24, 1952 AI' .Hy LP a Patented Aug. 3, 1954 UNITED STATES PATENT OFFICE SIIWPLIFIED ADJUSTABLE MAGNETIC HEAD ASSEMBLY Application April 24, 1952, Serial No. 284,194

(Granted under Title 35, U. S. Code (1952),

sec. 266) 3 Claims.

The invention described herein may be manufactured and used by or for the Government for governmental purposes without payment to me of any royalty thereon.

This invention relates to magnetic recorders and more particularly to an adjustable head assembly for magnetic recorders.

in the past it has been the customary practice either to nx the pole piece of the recording head rigidly at the desired distance from the recording medium or to use a differential screw adjusting support for the magnetic head. Since many magnetic recorders require that the magnetic head be adjustably mounted in order to vary the distance of the head with respect to the recording medium the problem of providing a suitable adjustable mount for the head has become more and more serious since the differential screw type of adjustable support requires very precise machining in order to permit line adjustments of the support.

It is an object of this invention to provide an adjustable head assembly for a magnetic recorder wherein motion of the head with respect to the supporting shaft will be permitted in three directions, namely, rotary, radial and axial.

A further object of this invention is to provide an adjustable head assembly wherein the supporting elements of the head need not be precision machined or cast.

A still further object of this invention is to provide an adjustable head assembly for magnetic recorders wherein two heads or pole pieces may be supported by a single head assembly while still permitting each of the heads to be properly positioned with respect to the recording medium.

The above objects as well as other objects, features and advantages of this invention will be more completely understood with reference to the following description when taken in conjunction with the drawings wherein:

Fig. 1 is a plan View of the adjustable head assembly constructed in accordance with this invention.

Fig. 2 is a top plan View of the adjustable head assembly constructed in accordance with this invention.

Fig. 3 is a cross-sectional View taken along line 3 3 of Fig. 1 showing double head construction.

Fig. 4 is an enlarged fragmentary View of one portion of the split color adjustable support.

Referring now to the drawings, the magnetic head 9 is suitably mounted on the support bracket I, as for example by clamping bar l. The sup- CII port bracket I is internally threaded at I0 and into those threads, screw member t is positioned. The support bracket I Yhas an opening therein defined by the guide surface I2 and the surfaces II and I5. A split collar 2 has surfaces I6 and il which mate with the support shaft 8. The split collar has a groove in one portion thereof into which the guide surface I 2 slidably fits. The other portion of the split collar has a groove into which a shoe member 5 slidably nts. The shoe member 5 is engaged by the screw 6 and will be moved toward and away from the groove surface of the split collar upon turning of the screw 6. The support member i may be made more rigid by incorporating a tie bar 4 as shown in the drawing.

The magnetic head assembly above described may be used with a magnetic recording medium such as a drum or tape I3. In order to permit the above described head assembly to be properly positioned with respect to the recording medium I3 a feeler gauge is placed on the recording surface of the recording medium. With the screw 6 turned such that shoe 5 is loosely engaging the split collar 2, the head assembly is moved so that the head or pole piece s rests on the feeler gauge. When the head assembly is so positioned, the screw 6 is adjusted to exert pressure on the shoe 5 which in turn causes pressure to be exerted on the shaft 8 and the guide surface I2 by the split collar 2 and by this pressure the head assembly is frictionally held against movement on the shaft 3. Preferably a lock nut I4 is provided to insure that the screw t does not release its pressure against shoe 5.

Referring now to Fig. 3, it Will be seen that the magnetic head assembly may consist of two separate heads or pole pieces on either side of the supporting bracket I.

It is oftentimes desirable to use an electrically nonconductive material for the support bracket I in order to minimize the number of parts required for mounting of the terminals 3. Where the magnetic head is of the type used for recording positive and negative pulses on the recording medium, three terminals are usually required for each head.

From the above description it will be apparent that the magnetic head 9 may be adjusted in the rotary and axial directions about the supporting shaft 8 when the screw 6 is loosened and may be adjusted in a radial direction of the shaft 8 by sliding in the grooves of the split collar 2.

Although only a single embodiment of this invention has been illustrated and described, it will be understood that many changes, additions and omissions may be made Without departing from the spirit and scope of this invention.

What iaclaimedis;

1. An adjustablyfmounted magnetic=r =:cr rdng" head assembly comprising, a support bracket having a magnetic recording head mounted thereon,

said support bracket having an opening therein which is defined by a guide surfacef.ansplliticolian having internal surfaces of such shape as tomate with a supporting rod and .anexternal suriface to mate with said guidensurfaceandscrew,

means engaging said support bracket and pesiftioned so as to exert force at right angles to said guide surface on the exterior-A surfacelv of saidV split collar whereby said support bracket will frictionally engage said split collar and said split collar will frictionally engage said-supportingrrod when said screw means exerts said force.

2. An adjustable support for a magnetic recordingr head;L comprising.; au. support bracket toa whichafmagnetierecordingrheadmaybe secured;4 saidf supporttbracketf, having anzopening, therein; i

said` opening: being;y dened; byr au' guide-.surface;. a split;4 collar having.; internal surfaces .to mate withza supportingzrod'iandfan;exteriorz'surfa'ceeto,

mate withl said: guide.s surface andl relasablef means engaging: said supporti bracket to-causezl saidzexterior surface: of: said split collar: tcniric: y

tionaily'engagersaidiguide surfacenandi said inefrom the other straight side of said U-shaped surface `tolthe edgeo said support bracket, a screw. member. enga-ging said threaded internal opgening-,andihaving-ga length suicient to extend yintro said cut away portion, a shoe member en- Agagedbysoddisfa-rev.' member when said screw .memberi-extends into said out away portion, a split collar having internal surfaces to mate with asupporting/frodiand a first external surface to mate with said guide surface and a second external surface to mate With a surface of said shoe member.; Y

leeterences Gited-.irv the Vrile,V of.v thief patent.

UNITED STATESPAEENI'S Number.

Blauw-2Y Date 1,7981572 Welton Mar. 31, 1931 1,854,478 Meyers Apr. 19, 1932 128833561.. Chipman Oct 18,'19324 2574367 P 'ettus Nov.'13', 1951' w" :n f 

